MultiWan + SquidGaurd = Proxy reports Unable to reach URL

[Visseroth]

OK, so was working on a clients network tonight because of a strange issue where some machines would go offline for a few minutes, sometimes as long as 20 minutes then come back online. Spent a few hours out there tonight trying to figure out what was going on. Reset to factory defaults, setup all the packages again only to find the a similar thing happening when a WAN is taken offline Squid reports that it is unable to reach the URL.

Setup consists of two (different) ISPs
One LAN
Snort
Squid
Squidguard

To resolve the issue I had to take SquidGuard offline then the URLs resolved just fine.

I did a quick google search where someone else had a similar issue and he/she seemed to resolve it by changing out the NIC from a realtek chipset to a intel chipset which seemed to resolve their issue and that is a possibility on this router as it has a USB NIC on one WAN because there are no further PCI slots available.

Any thoughts on why squidgaurd would have an issue with a multiwan setup? This is my only client with a multiwan setup. All my other clients have had no issues but they all run single wan's.